It’s almost impossible to overstate how wildly and wackily irresponsible DART’s latest plan for making up its billion-dollar goof truly is. One month they thought building rail lines to suburban Irving and Rowlett would cost $1 billion dollars. Next month they said, “No, two.” Billion.

Oops.

So this week, one of the ways they proposed making up the money was by taking a third of a billion dollars away from the planned second downtown rail alignment and the new South Oak Cliff line to the University of North Texas campus and the inland port.

If DART completes all the rail lines it has underway now and sticks to the plan of routing them all through downtown -- and if they fail to have a second line through downtown ready to handle that new train traffic -- downtown Dallas will be a parking lot. You won’t be able to drive across town. You won’t be able to walk across town.

That’s why DART had to sign a contract years ago with Dallas promising to build the second downtown line so it will be up and running as soon as it is needed. That’s what they’re trying to wriggle out of now because of their horrible money problems.

But wait! To be fair, the DART staff said they were pretty sure they might be able to find some more money later to re-fund those projects probably. That’s like a former in-law of mine who said to me, “I will pay you back this money if there is any possible way I can.” (Picture me lunging forward with both hands and snatching back my green.)

So today the entire city council and the mayor signed a letter “encouraging” the DART board “to seek other alternatives that will not postpone or otherwise reallocate funding from the Downtown and Oak Cliff projects.” I think city council transportation and environment chair Linda Koop had something to do with getting it together, but I’m waiting on some call-backs to confirm that.

Still, ‘bout time. Now let’s do something really responsible and insist on an outside audit. Can you imagine? It’s about a billion. No, wait! It’s more like two.